Boundary line

The set of points where the two sides of a two-variable linear inequality are equal.

Slope

A measure of the steepness of a line on a graph, the rise divided by the run.

Constant of proportionality

A constant ratio of two variables related proportionally.

Direct variation

A relationship between two variable in which the data increase or decrease together at a constant rate.

Linear equation

An equation whose solutions form a straight line on a coordinate plane.

Linear inequality

A mathematical sequence using < >≤≥ whose graph is a region with a straight line boundary.

Standard form

A way to write numbers by using digits.

Point slope form

The equation of a line in the form of Y_2-Y_1=m(X_2-X_1) where m is the slope and (X_(1,),Y_1) is a specific point on the line.

Slope intercept form

A linear equation written in the form y=mx+b, where m represents slope, and b represents the y-intercept.

X-intercept

The x-coordinate of the point where the graph of a line crosses the x-axis.

Y-intercept

The y-coordinate of the point where the graph of a line crosses the y-axis.